1. Field of the Invention
The invention pertains to optoelectronics generally, and more specifically to an apparatus optimized for both optoelectronic component testing and subsequent assembly to close tolerance.
2. Description of the Related Art
Optoelectronic devices offer much potential advantage over their purely electrical counterparts in speed of operations and in immunity to external interference. However, one obstacle which has prevented widespread use is the relative difficulty in making a high quality optical interconnection as opposed to the simplicity of the modern electrical connectors. Connections are generally made using lenses and fibers. The lenses and fibers are typically placed and aligned by robotic systems to attain the necessary precision.
The mechanical alignment of the prior art is not a process amenable to high volume, low cost production techniques. Recently, several disclosures have suggested that silicon may be used as a substrate material upon which the optoelectronic components and waveguides may be placed. By anisotropically etching the silicon, or with other well-known techniques from the semiconductor industry, v-grooves may be formed into the silicon with great precision. These v-grooves are used in the prior art to assist in the placement and alignment of optical fibers to optoelectronic components, the formation of optical waveguide to optical waveguide interconnection, and similar applications. While these uses of the silicon technology are valuable for the intended applications, the prior art fails to address the issues associated with device yield.
Optical devices are often expensive. Additionally, these devices suffer from yield problems that may go undetected until after final assembly and burn-in. While this problem exists with silicon integrated circuits used for purely electronic applications, the cost of re-working an optoelectronic component is generally much greater. The component must be removed from an aligned location, a new component placed with great precision, and the new component attached without subsequent movement or repositioning of neighboring devices. All processes must be completed without contamination or destruction of neighboring optical components.
Where there are a number of components which must all be aligned together, the failure of one of these components can add very greatly to the cost of assembly. Further, the chances for successful rework are diminished in view of the risk of contamination or disruption of alignment. Yet the likelihood of rework is greater with more optoelectronic components. The combination of higher cost to rework, lower expected yields, and lower rework yields result in exponentially increasing costs as more optoelectronic devices are combined in close proximity.